Process for preparing disazo dyes with bis-anilino methane coupling component
Abstract
Abstract A process for preparing a disazo dye represented by the following formula: <IMAGE> wherein R1 and R2 each represents a hydrogen atom, a halogen atom, a nitro group, a trifluoromethyl group, a lower alkoxycarbonyl group or a lower alkylsulfonyl group, R3 represents a lower alkyl or allyl group which may optionally have a substituent or substituents, and R4 represents a lower alkyl or allyl group having a substituent or substituents, which comprises diazotizing an amine represented by the following formula: <IMAGE> wherein R1 and R2 are the same as defined above, and coupling the diazotized product with a bis(N,N-di-substituted anilino)methane represented by the following formula: <IMAGE> wherein R3 and R4 are the same as defined above.
Inventors
- 👤 Toshio Niwa
- 👤 Kiyoshi Himeno
- 👤 Shuichi Maeda
- 👤 Yukiharu Shimizu
Bibliographic Details
Claims Analysis
Total Claims: 2References Cited (Backward Citations)
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